Vakarewa, 19, has impressed the selectors with her pace and performances for the Shooting Stars, while Aley, 32, will add some experience to the group and if she plays, will become Australia's oldest women's ODI debutant in nearly 45 years.
"This is going to be one of the most tightly contested World Cups in recent times and we have chosen 15 players that we believe are capable of leading Australia to victory," national selector Shawn Flegler said.
"Belinda Vakarewa is an exciting young talent who has made the most of her opportunities that have come her way with the Shooting Stars and more recently during the three-week camp held in Brisbane. She adds some extra firepower with her pace and we're excited to see what she can do.
"Sarah Aley will also add some extra depth to our bowling attack and brings an incredible amount of experience to the group which is invaluable in a tournament like this.
"Ashleigh Gardner is another young player that has really impressed and alongside Kristen Beams, Jess Jonassen and Amanda-Jade Wellington, will form a strong spin attack that provides a range of options with the ball.
"We're pleased to have Rachael Haynes back in the squad after suffering an ankle injury earlier in the year and she too brings a wealth of experience having played in World Cups and in English conditions.
"This is an incredibly exciting time for this team, with the chance to stake their claim as one of the most successful sporting teams in Australian sport."
Australia are the defending champions, having won a record sixth Women's World Cup title in India in 2013, when they defeated West Indies in the final.